A political thriller is typically set against the backdrop of a political power struggle, rampand corruption or a "deep state" conspiracy. The stakes in these stories are usually immense, and the fate of a country is often in the hands of one singel individual. Political corruption, organized crime, terrorism, intelligence operations, secret military commands, and warfare are common themes.
The modern political thriller came to life in the early days of the Cold War. Graham Greene's "The Quiet American" (1955) tells about the American involvement in Vietnam during the First Indochina War. Richard Condon's "The Manchurian Candidate" (1962) is set in the aftermath of the Korean War and the days of McCarthyism. In Frederick Forsyth's "The Day of the Jackal", an assault on Charles de Gaulle has to be prevented.
While many of these early political thrillers where focused on espionage, more recent thrillers often deal with government corruption or conspiracies at the highest political level.
More on Wikipedia